Latest Issue
Volume 0 ， Issue 3 ， 2000
- Abstract：To construct ScFv and Fab from murine anti gastric cancer monoclonal antibody（mAb）3H11. Methods.At first,3H11 ScFv and Fab were constructed with V genes PCR amplified by degenerate primers for FR1.The bacterial expressed 3H11 Ab fragments showed no antigen binding activity.Then,phage antibody library and random mutated library were constructed from 3H11 hybridoma cells and panning selection was performed.Again the identification of positive clone was failed.Finally the N terminal sequences of V regions were resumed to 3H11 original sequences by site directed mutagenesis via PCR. Results.Binding activity to gastric cancer cells was detected only from N terminal sequence corrected 3H11 ScFv and Fab,though the expression of the Ab fragments was not affected.Correction of either VL or VH N terminal sequences could partially resume the antigen binding activity. Conclusion.Sequence changes of V region N terminal introduced by PCR may seriously affect antigen binding without affecting the expression of antibody.Keywords：gastric cancer;Fab;ScFv;PCR4|13|3Updated：2024-04-10
- Abstract：The anti atherosclerotic effect of fluvastatin at doses insufficient to lower serum cholesterol on the catheter induced intimal thickening and possible mechanism were investigated in abdominal aorta of rabbits. Methods.Fifty six rabbits were randomly divided into eight groups（n=7,each）.Fluvastatin was given mixed with food at daily dose of8mg/kg starting 5 days before catheterization.Light microscope,immunohistochemistry,transmission electron microscope and RT PCR assay were applied to assess vascular smooth muscle cell （VSMC）proliferation and apoptosis, as well as oncogene expression in vascular wall. Results.At day 10 and day 15 after catheter induced denudation intima/media（I/M）thickness ratio was obviously higher, and also the percentage of PCNA positive cells and TUNEL positive cells in media was significantly higher compared with controls.The intimal hyperplasia was mostly composed of α SM actin positive cells.In rabbits given fluvastatin I/M ratio and the percentage of these positive cells significantly decreased compared with those without fluvastatin.The overexpression of proto oncogene H ras mRNA and decreased expression of anti oncogene p53 mRNA were found after vascular injury,whereas fluvastatin significantly reduced H ras mRNA and increased p53 mRNA expression. Conclusion.Proliferation of VSMC in the media and the migration to the intima can be inhibited,and apoptosis of VSMC be induced by short term use of fluvastatin after balloon catheter denudation,independent of serum lipid change.The underlying mechanism is presumably associated with the influence of fluvastatin on oncogene expression in the injured vascular wall.Keywords：HMG CoA reductase inhibitor;smooth muscle cells;apoptosis4|8|0Updated：2024-04-10
- Abstract：This study characterized the activation of platelet integrin α bβ3 induced by two anti human platelet tetraspanin monoclonal antibodies（mAbs）,HI117 and SJ9A4. Methods.Using 125 I labeled human fibrinogen（Fg）,specific Fg binding to human platelets induced by HI117 and SJ9A4 was measured as indication of activation of platelet integrin αbβ3 by the two mAbs. Results.HI117 and SJ9A4（10μg/ml and 20μg/ml） induced evident specific Fg binding to human platelets,suggesting that the two mAbs evoked activation of platelet integrin αbβ3.Further study indicated that HI117 and SJ9A4 induced integrin αⅡbβ3 activation independent of platelet Fc receptors, and that HI117 and SJ9A4 induced integrin αbβ3 activation was inhibited by sphingosing, aspirin, apyrase, and/or PGI2. Conclusion.The anti platelet tetraspanin（CD9）mAbs,HI117 and SJ9A4, can induce platelet integrin αⅡbβ3 activation independent of Fc receptors.Three signaling pathways,i.e.thromboxane,secreted ADP, and cAMP pathways may be involved in the process,with protein kinase C activation presumably being the common step of the three pathways.Keywords：platelets;integrin α bβ3;tetraspanin4|23|0Updated：2024-04-10
-
- Abstract：To investigate the effects of coxsackievirus B 3（CVB 3） on ion channel currents in rat ventricular myocytes. Methods.Rat hearts were isolated with collagenase to acquire single ventricular myocytes, L type voltage dependent calcium channel（VDCC）current （I Ca ）,Na + current （I Na ）, outward potassium current （I out ）, inwardly rectifying potassium current（I KI ） were recorded using whole cell patch clamp techniques. ResultsCVB 3 infection increased I Ca and I out , while decreased I KI ; but it had no obvious effect on I Na . Conclusion.The effects of CVB 3 on I Ca 、 I out 、 I KI may be one of the mechanisms of myocytes damage and the occurrence of abnormal electroactivities induced by CVB 3 infection.Keywords：coxsackievirus B3;cardiomyocytes;ion channel current4|15|1Updated：2024-04-10
- Abstract：To investigate the dynamic changes of serum vascular endothelial growth factor（VEGF） levels in a rat model of acute myocardial infarction. Materials and methods.Eighty eight adult male Sprague Dawley rats weighing approximately 270 g were used in this study. Eighty rats were subjected to left coronary artery ligation, with 8 rats for each different duration of infarct. Eight sham operated animals in which the left coronary artery was surgically exposed without ligation were used as controls. Blood samples were drawn from the right atrium before （sham animals） and 1,3,6,12,24 h and 2,3,5,7,14 d after myocardial infarction. The concentrations of serum VEGF were measured by a sensitive enzyme linked immunosorbent assay with a rabbit polyclonal antibody specific for VEGF. Results. In the 8 control animals, the mean concentration of serum VEGF was 66.99±17.83 pg/ml. Six hours after myocardial infarction, the level of serum VEGF significantly increased to 125.68±28.07 pg/ml （P<0.01 vs. sham controls）, and reached a peak （240.61±70.63 pg/ml. P<0.01 vs. sham animals） at 24 h after ligation and then decreased gradually over the remaining 2 weeks. However, the level remained significantly elevated for 14 d （107.64±30.13pg/ml, P<0.01 vs. sham controls）. Conclusion. The present study shows that the levels of serum VEGF are markedly increased until 14 d in the rat model of acute myocardial infarction. The increased serum VEGF level may play an important role in the angiogenesis associated with myocardial infarction.Keywords：myocardial infarction;vascular endothelial growth factor;enzyme linked immunosorbent assay4|7|3Updated：2024-04-10
- Abstract：Background. Our previous studies indicated that the increased arginine vasopressin（AVP） in ischemic brain regions of gerbils could exacerbate the ischemic brain edema. This experiments is further clarify the relation between AVP and cerebral ischemia at the molecular level. Methods. The contents of AVP, AVP mRNA, AVP immunoreactive（ir） neurons in supraoptic nucleus（SON） and paraventricular nucleus（PVN） after cerebral ischemia and reperfusion were respectively determined by radioimmunoassay（RIA）, immunocytochemistry（ⅡC）, situ hybridization and computed image pattern analysis. Results. The contents of AVP in SON, PVN were increased, and the AVP ir positive neurons in SON and PVN were also significantly increased as compared with the controls after ischemia and reperfusion. And there were very light staining of AVP ir positive neurons in the other brain areas such as suprachiasmatic nucleus （SC） and periventricular hypothalamic nucleus （PE）, but these have no significant changes as compared with the controls. During different periods of cerebral ischemia （30～120 min） and reperfusion （30 min）, AVP mRNA expression in SON and PVN were more markedly increased than the controls. Conclusions. The transcription of AVP gene elevated, then promoting synthesis and release of AVP in SON, PVN. Under the specific condition of cerebral ischemia and reperfusion, the activity and contents of central AVP increased abnormally is one of the important factors which causes ischemia brain damage.Keywords：cerebral ischemia;arginine vasopressin;gene expression4|16|1Updated：2024-04-10
- Abstract：The aim of this study is to investigate the functional relationship between filamin, a known actin binding protein, and myosin and the effects of filamin on the interaction between myosin and actin. Methods.Ultra centrifugation method was used to investigate the binding of filamin to both phosphorylated and unphosphorylated myosins. Mg ATPase activities of both phosphorylated and unphosphorylated myosins in the presence and absence of actin were measured to observe the effects resulted from filamin actin and filamin myosin interactions. Results. It was found that filamin is also a myosin binding protein. Filamin inhibited the actin activated Mg ATPase activity of phosphorylated myosin and stimulated Mg ATPase of phosphorylated myosin in the absence of actin; in addition, filamin stimulated Mg ATPase activity of unphosphorylated myosin in both the presence or absence of actin. Conclusion. The results suggest that the effects of filamin on the myosin Mg ATPase activities are bi directional, i.e., stimulatory via binding to myosin and inhibitory via binding to actin.Keywords：bi directional regulation;myosin binding;myosin actin interaction4|16|4Updated：2024-04-10
- Abstract：Aim. To study the effect of kanglemycin C （KC） on production and gene transcription of lymphokins. Methods.Cell proliferation and lymphokin activities were quantified with MTT colorimetry and ELISA, and gene transcriptions of lymphokins semi quantified with RT PCR. Results.Suppression of KC on proliferation of enriched T and B cell respectively mediated by Con A and LPS was declined by addition of exogenous IL 1, IL 2, and IL 6. KC 80 nmol/L markedly inhibited IL 2 and IL 6 production and mRNA transcription of incubated mouse splenocytes induced by Con A. Additionally, KC had some suppression on IL 1β and IL 6 productions of peritoneal macrophage stimulated by LPS （5μg/mL）, whereas cyclosporine （CS） had not. [WT5”BX]Conclusion. [WT5”BZ]Immunosuppression of KC came true partially through the decrease of IL 1β, 2 and 6 productions, especially of IL 2. However, CS′s immunosuppression was mainly through the decrease of IL 2 procduction.Keywords：kanglemycin C;cyclosporine;lymphokin RT PCR4|15|0Updated：2024-04-10
- Abstract：To investigate the expression of telomerase gene hTRT mRNA in HeLa cells and to obtain hTRT protein for futher study Methods. The gene for encoding hTRT catalytic domain was cloned based on RT PCR amplification from HeLa cells and sequenced The cloned hTRTcDNA was in frame inserted into His tag fusion expression vector pEK318 The His tag hTRT fusion proteins were purified by Ni NTA chromatography and stained by western blotting Results. An approximately 620bp fragment was generated and cloned into pBluescript SK+between SalI and BamHI sites DNA sequencing showed the isolated fragment was consistent to those reported SDS PAGE present that a 17kDa protein was expressed stably in E coli JM109 harboring pEKTRT344 containing 6×His tag and hTRT 150aa, and the expression level of the protein was about 26% of the total bacterial proteins, while the expression of pEKTRT containing 6×His tag and hTRT 243aa was only detectable as 27 kDa band in western blotting Both of fusion proteins were purified by Ni NTA chromatography and showed single band（>95% purifity） in Coomassie Brilliant staining Western blotting confirmed that two proteins could be recognized by the Ni NTA AP conjugate Conclusions. The hTRT catalytic domain was highly conserved The expressed hTRT protein contained recognizable His tag, telomerase specific and strong antigenic epitops, which may be convenient for further investigationKeywords：telomerase;human telomerase reverse transcriptase;expression;E coli4|14|0Updated：2024-04-10
- Abstract：Patients with Graves’ disease （GD） have marked lymphocytic infiltration in their thyroid glands We examined the gene for the variable regions of the α chain of the Chinese T cell receptor（V α gene） in intrathyroidal T cells to determine the role of T cells in the pathogenesis of GD and offer potential for the development of immunotherapeutic remedies for GD Methods. We used the reverse transcription and polymerase chain reaction（RT PCR） to amplify complementary DNA（cDNA） for the 18 known families of the V α gene in intrathyroidal T cells from 5 patients with Graves’ disease The findings were compared with the results of peripheral blood T cells in the same patients as well as those in normal subjects Results. We found that marked restriction in the expression of T cell receptor V α genes by T cells from the thyroid tissue of Chinese patients with GD（P<0 001） An average of only 4 6±1 52 of the 18 V α genes were expressed in such samples, as compared with 10 4±2 30V α genes expressed in peripheral blood T cells from the same patients The pattern of expressed V α genes differed from patient to patient with no clear predominance Conclusions. Expression of intrathyroidal T cell receptor V α genes in GD is highly restricted suggesting the primacy of T cells in causing the disordersKeywords：T cell receptor;Vα gene;Graves disease4|4|0Updated：2024-04-10
- Abstract：To observe the effects of closed reduction and percutaneous K wires fixation of displacd supracondylar humerus fracture in children MethodsRetrospective review of fourteen patients who sustained displaced supracondylar fracture of distal humerus treated by closed reduction and percutaneous K wires fixation Results. All patients’ K wires were removed at 4 weeks post operation Their elbow function regained at 8 weeks The average period of followed up was 10 month （varies from 6 to 18 month）, all fractures healed very well without any permanent complications Two transient nerves palsy,ulnar and radial nerve each, recovered completely at 12 weeks and 16 weeks post operation respectively Conclusion. Closed reduction and percutaneous K wires fixation is a safe and efficient treatment for displaced humerus surpracondylar fracture in childrenKeywords：closed reduction;percutaneous k wire;supracondylar humerus fracture4|17|0Updated：2024-04-10
- Abstract：To evaluate the results of operative treatment of spinal fracture dislocation without neurologic deficits. Methods.Eighteen patients with spinal fracture dislocation were neurologically intact at the time of injury, and all were treated operatively. The fracture sites were:8 cases in cervical spine, 3 cases in thoracic spine, and 7 cases in lumbar spine. Eight patients with cervical injuries had variant degrees of forward slide and kyphotic deformity. Of the 10 thoracic and lumbar fractures, one had lateral dislocation, 4 cases with kyphotic deformities, 5 cases with spinal canal compromise averaged 50% （ranging from 40% to 70%）. Results.The average period of follow up was 4.4 years with a range of 11 months to 13 years. All the patients returned to full time work. No patient developed neurologic deterioration. Kyphotic deformity was corrected in the 4 cases, and no progressive kyphosis was noted. There was no operation related complication. The averaged post operative hospitalization time was 13 days. Conclusions. Despite the rare incidence of spinal fracture dislocation without neurologic deficits, we suggested that kind of fracture be considered unstable fracture because of its potential risk of delayed neurologic deterioration and kyphotic deformity, and be treated operatively to restore the sagittal alignment and the stability of the spine.Keywords：operative treatment;spinal fracture dislocation4|19|7Updated：2024-04-10
-
- Abstract：To undertake the pilot experiments of prevention of disability （POD） in 14 different geographical areas to serve as examples for future development of rehabilitation work in China and in Asia. Methods.According to the principles and national criterion, 27 000 people affected by leprosy were selected and assessed using disability record forms at beginning and followed up regularly for observing changes of different indicators. Results. A total of 197 neuritis cases were detected and treated with prednisolone out of 1 407 new or active cases. Self care training of eyes, hands and feet were conducted for 10 500 disabled people affected by leprosy. Comprehensive therapy was given to 1 804 cases having complicated ulcers of which 1 055 cases have got their ulcers healed. Out of 706 prostheses, 613 were given to patients with satisfactory results. Surgical treatment was given to 269 cases and 251 have shown good progress. Conclusion. Most of patients have got benefit from the project in function or appearance which is very helpful for their going back to the society and agreed by foreign experts during the final evaluation. The experiences from the project can be implemented in the whole country.Keywords：leprosy;rehabilitation;disability4|15|6Updated：2024-04-10
- Abstract：To investigate the cold preservation effect of rat livers by modified storage method with self made HYD solution. Methods. The modified method was that the vascular bed of rat livers was expanded with an additional 20 to 40ml self made HYD solution/100g liver. After removing the liver, the extra HYD solution expressed as % liver weight was entrapped via portal infusion by tying off the supra and infra hepatic inferior vena cava. According to the amount of extra HYD solution, 40 rats were randomly divided into four groups including: control group with conventional storage method, 20% group, 30% group and 40% group. The preservation effect of modified storage method with that of conventional storage method by using isolated perfused rat liver model was compared. [WT5”BX] Results.[WT5”BZ] Bile production and all the indices of hepatic microcirculation including portal perfusion pressure, endothelin 1 in the effluent, trypan blue distribution time and histology in modified method groups were significantly superior to those in control group （P<0.05）. The liver enzymes in 30% group were markedly lower than those in control group （P<0.05）. The preservation effect of rat liver in 30% group was the best among the modified method groups. Conclusion. The modified cold storage method is effective and may have potential for clinical application for liver preservation.Keywords：liver preservation;HYD solution4|15|0Updated：2024-04-10
- © 2024 Chinese Academy of Medical Sciences 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0